1. Field of the Invention
The embodiment disclosed herein relates to a rotating electrical machine control apparatus and a rotating electrical machine system.
2. Description of the Related Art
There has been available a motor control apparatus that controls a rotating electrical machine such as a motor or a generator by detecting, with a position sensor such as an encoder, the rotation position of the rotating electrical machine. The position sensor outputs an absolute signal that indicates the rotation position of the rotating electrical machine, an incremental signal that indicates the amount of change of the rotation position of the rotating electrical machine, and the like, and the motor control apparatus obtains the rotation position of the rotating electrical machine on the basis of the signals output from the position sensor.
The rotating electrical machine control apparatus and the position sensor are connected to each other by a plurality of signal lines. Thus, a wiring error, for example, may occur in the signal lines. In the case where there is a wiring error in the signal lines, the rotation position of the rotating electrical machine is not normally obtained, thereby making it difficult to control the rotating electrical machine. In addition, the situation where the rotation position of the rotating electrical machine is not accurately obtained may occur due to a cause other than a wiring error. Also in this case, it may become difficult to control the rotating electrical machine.
To this end, there has been proposed an abnormality detection device that detects an abnormality in signal lines by comparing the amount of change of the absolute position of a rotating electrical machine, which is obtained from an absolute signal, with the amount of change of the relative position of the rotating electrical machine, which is obtained from an incremental signal (for example, see Japanese Unexamined Patent Application Publication Nos. 4-62420 and 3-100411).
There are various specifications for a position sensor used to control a rotating electrical machine. In addition, sensorless control that dispenses with a position sensor is possible for some types of rotating electrical machines. Therefore, there has been available a rotating electrical machine control apparatus in which a position information generator that generates position information indicating the rotation position of a rotating electrical machine on the basis of a signal from a position sensor is addable as an option substrate (for example, see Japanese Unexamined Patent Application Publication No. 2008-108094).
However, if the above-mentioned abnormality detection device is provided in the position information generator, the configuration of the position information generator becomes complicated, thereby increasing the manufacturing cost.